Probe Holder Worm Gear Locking for Precise Rotary Positioning

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing surface measuring instruments face high manufacturing costs and complexity due to the need for backlash-free gearboxes and electromechanical drive trains, which also generate undesirable thermal effects.

Innovation Solution

The use of a worm gear with detent devices to lock the probe holder in predefined rotational positions, eliminating backlash and reducing manufacturing costs while ensuring high reproducibility and accuracy.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If a backlash-free gearbox is used in the electromechanical drive train, then the rotational position reproducibility is improved, but the manufacturing cost and device complexity increase significantly

Engineering Contradiction:
Improverotational position reproducibilityVSAvoiddrive train complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent replaces the complex mechanical backlash-free gearbox with a different mechanical approach: a worm gear combined with a detent locking mechanism. The worm gear provides the necessary torque multiplication while the detent mechanism (with locking elements and locking recesses) ensures precise rotational positioning without requiring a complex gearbox design. This substitution resolves the contradiction by achieving positioning precision through a simpler, more cost-effective mechanical system.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

2Measurement precision

If a brake is used to rotate the probe holder against thermal effects, then the rotational position reproducibility is improved, but heat generation and energy consumption increase

Engineering Contradiction:
Improverotational position reproducibilityVSAvoidheat generation
Core Design Contradiction:
Measurement precisionVSObject-generated harmful factors

Solution Approach 1:

The patent replaces the brake-based mechanical system with a worm gear and detent locking mechanism. The worm gear inherently provides self-locking capability due to its friction characteristics, eliminating the need for additional braking components. The detent mechanism with multiple locking recesses ensures precise positioning without generating heat. This substitution resolves the contradiction by achieving rotational position reproducibility without the harmful thermal effects associated with brake engagement.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

3Measurement precision

If a high torque drive train is used to overcome brake engagement, then the rotational position control is improved, but the power consumption and energy loss increase

Engineering Contradiction:
Improverotational position controlVSAvoiddrive train torque
Core Design Contradiction:
Measurement precisionVSPower

Solution Approach 1:

The patent replaces the high-torque brake-based system with a worm gear mechanism that naturally provides mechanical advantage through its gear ratio. The worm gear's self-locking property allows the system to maintain rotational position without requiring continuous high torque. The detent locking mechanism further reduces the torque needed to maintain position by providing discrete locking points. This substitution resolves the contradiction by achieving precise rotational position control with reduced power requirements compared to a brake-based high torque system.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

A cost-effective and robust surface measuring instrument with precise rotary positioning is achieved, simplifying assembly and enabling manual retrofitting, while eliminating mechanical play in the drive train.

Implementation Method 1

the drive train has a worm gear

Methodology Applied
Scientific EffectWorm drive: Worm Drive

Implementation Method 2

locking means for locking the button holder in predefined rotational positions are assigned to the button holder

Methodology Applied
Scientific EffectMechanical locking: Mechanical Fastener

Data Source

PatentEP4345410B1Surface measuring apparatus
Publication Date: 2025.11.19 JENOPTIK IND METROLOGY GERMANY
  • EP4345410B1 patent drawingFigure 1
  • EP4345410B1 patent drawingFigure 2
  • EP4345410B1 patent drawingFigure 3

AI summary

A surface measuring instrument 2 has a base body 4 and a probe holder 10 for a probe of the surface measuring instrument 2, which is rotatably mounted relative to the base body 4 about a rotational axis and is rotatably driven by means of an electromechanical drive train 6. The drive train 4 has a worm gear 20, wherein the probe holder 10 is assigned locking means 22 for locking the probe holder 10 in predefined rotational positions.